We seem doomed to experience more government anti-obesity campaigns and policies that have little effect on our collective weight – but do have a huge impact on individuals, increasingly judged and condemned on the basis of their appearance.

The demand for weight-loss pills and surgeries, fuelled by the notion that everyone has a moral obligation to achieve a slim body, will continue to eat up more and more of increasingly precious NHS budgets. This is what awaits us (or worse), if we don't change direction and stop trying to follow the one-size-must-fit-all method of healthcare.

Health researchers and professionals who have become disenchanted with the failure – and dangers – of a traditional weight-centred approach to health are increasingly adopting the Health At Every Size (HAES) philosophy. HAES promotes tested and achievable ways to optimise health for individuals and populations. It does this at an individual level by focusing on eating, activity and body acceptance. Of course, food and exercise are old targets in the health promoter's arsenal, and psychological factors influencing dieting behaviours are well-known. So what's new? The crucial difference is that HAES emphasises the benefits of sound nutrition, active living and body confidence as ends in themselves, not as a route to weight management.

Having removed the goal of weight loss, HAES promotes a healthy relationship with food, including the importance of learning to recognise internal signals rather than ignore them in favour of rigid eating plans. HAES encourages activity for general wellbeing, for pleasure in movement and abilities and not as a calorie-burning mission.

The hardest leap for practitioner and client alike can be the idea that all bodies are worthy of respect; that it is permissible and important to appreciate and care for the body you live in, whatever size you are; that bodies should not be disliked or despised for their lack of conformity to a particular size or shape.

Adopting a HAES approach may or may not result in a weight change, but that's not the point. The point is that HAES improves health outcomes long-term and dieting doesn't. That makes HAES the ethical, effective choice.

The evidence for favouring HAES over weight-loss interventions is strong. First, as has been documented in detail in several books, including The Diet Myth by Paul Campos and The Obesity Epidemic by Michael Gard and Jan Wright, the common obesity scaremongering in the media greatly exaggerates the risks. Over the last few decades, the UK population has got slightly fatter (and taller too, but no one seems to be worried about that), and ironically, longer-lived. Statistically speaking, being far from the average weight does result in an increased health risk, but this is small: the difference in life expectancy between the unusually fat or thin person and the medium-sized person is similar in magnitude to that of being male v female, or living in one neighbourhood v another, or habitually driving to work rather than cycling.

Second, whatever the risks of a particular weight, the scientific evidence is clear: for the vast majority of people, there is no known safe way to obtain significant weight changes and maintain them in the long-term. Dieting puts bodies in emergency starvation mode and, just as it is difficult to hold your breath for a long time, it is difficult to willingly undereat; your body will make you eat, just as it will make you breathe, in order to survive. The evidence shows that weight lost from dieting is almost always regained within a few years, often accompanied by a few more pounds. Weight loss pills (at least, those that haven't been found unsafe yet) result in a few pounds lost, but only while you continue them. Even those who undergo the risks of weight-loss surgery find that much of the weight lost is regained in the long term. On the other hand, many naturally thin people cannot manage to gain weight for sustained periods either, no matter how much they try to eat.

It is counterproductive to continue pouring money and effort into attempts to make everyone slim, especially when this results in side-effects that are disastrous for mental and physical health: widespread body dissatisfaction and poor self-image; eating disorders; appearance-based prejudice, discrimination, stigmatisation, and abuse. None of this promotes good health within the UK population. It also diverts attention from underlying influences on health: poverty, for example.

Instead let us aim for a more ethical approach: treating people of all shapes and sizes with respect and providing equal access to evidence-based healthcare without discrimination or prejudice. HAES, adopted by increasing numbers of researchers and healthcare professionals, provides just such an approach.